Lifting device.



No. 788,630. PATENTED MAY 2, 1905.

" G. W. COLEMAN.

LIPTING DEVICE.

APPLICATION FILED NOV. 21, 1904.

Patented May 2, 1905.

PATNT FFICE...

LlFTlhlG DEVIICE.

-SPECIFICATION forming part of Letters Patent No. 788,630, dated May 2, 1905.

Application filed November 21, 190 1. Serial No. 283,622.

Be it known that l, CLARENCE WVILLIAM COLEMAN, a citizen of the United States, and whose residence and post-office address is Vvestfield, Union county, State of New Jersoy, have invented certain new and useful lmprovements in Lifting Devices, of which the following is a specification.

This invention relates to improvements in lifting devices, and specially such as are adapted for use as lifting-jacks for automobiles and other heavy vehicles.

The invention seeks to provide an arrangement whereby the operation of a lever under one condition may be made to advance the thrust-piece of the lifting device and whereby the operation of said lever under another condition maybe made to retract said thrustpiece.

The invention also seeks to provide an arrangement whereby each movement of thelever will either advance or retract the thrustpiece, as the case may be, so that there will be no lost motion in the operation of the lever.

1n the accompanying drawings, forming part of this specification, and in which like reference-numerals designate corresponding parts in the several views, the preferred embodiment of the invention is represented.

Figure 1 is a vertical sectional elevation of the lifting device. Fig. 2 is a sectional plan view taken on the line 2 2 of Fig. 1.- Fig. 3 is a sectional plan view on the line 3 3 of Fig. 1. Fig. 4 is a sectional elevation of the upper end of the lifting device, showing the parts in the position for retracting the thrust-piece. Fig. 5 is an elevation of the upper portion of the lifting device and showing the lever as it is operating to retract the lifting device.

Referring now to the particular embodiment of the invention as the same is shown in the drawings, 1 is a tubular standard containing the thrust-piece 2, provided with a seat 3 at its upper end and adapted to be advanced out of or retracted into the standard. The

thrust-piece is provided with two oppositelydisposed sets of rack-teeth 5 6 7 8, &c., and 5 6 7 8, &c.

9 is a lever provided with a handle 10 and pivotally secured to the standard by pivotpins 11 and 12. The pivoted end of the lever 9 surrounds the standard, as shown, and is provided. with two dogs 13 and 14:, mounted on the pivots 15 and 16, respectively, so that the dogs face the two sets of rack-teeth in the thrust-piece.

In the preferred arrangement the lever 9 is pivoted near the upper end of the standard, so that the dogs 13 and 14 project above the upper end of the standard, as shown in the drawings. The dogs are provided with springs 17 and 18, which tend to keep the dogs pressed against the thrust-piece.

19 is a ring rotatable on the boss 20, formed on the standard. This ring carries pivoted pawls 21 and 22, which afford abutments to cooperate with the dogs 13 and 1 1, as will be presently explained. These pawls 21 and 22 are pivoted at their lower ends and are set in recesses 23 and 24, formed on the ring 19. Springs 25 and 26 tend to keep these pawls pressed inward. The dogs 13 and 14 have projections 27 and 28, adapted to cooperate with the pawls 21 22, as will be presently explained.

29 is a spring-latch working in an extension 30, formed on the ring 19, which latch is adapted toenter one of the recesses, such as 31, on the standard to hold the ring against accidental displacement.

in the operation of the device when the thrust-picce is intended to be advanced the ring 19 is turned so as to bring the pawls 21 and 22 out of alinement with the dogs 13 and 14--that is, out of cooperating position with reference to said dogs. (See Figs. 1, 2, and The lever 9 is then rcciprocated up and down. When the lever moves up, the dog 14, in engagement with the tooth 7, lifts the thrust-piece 2 up until the dog 13 engages the tooth 8. The lever is then pushed downward, whereupon the thrust-piece is elevated again until the dog 14: engages the tooth 8. Thus the thrust-piece is advanced step by step and for each movement of the lever. When the thrust-piece is to be retracted, the ring 19 is turned round, so as to bring the pawls 21 and 22 into alinement with the dogs 13 and la that is, into cooperating position with reference to said dogs, as shown in Figs. 1 and 5.

Referring now to Fig. 1, when the lever 9 is now moved downward thrust-piece 2 is slightly retracted and dog 13 is elevated until the dog 13 has engaged the tooth 7 and taken the weight of the thrust-piece. During this movement the projection 28 abuts against the pawl 22 and the pawl yields until the weight of the thrust-piece is transferred to dog 13, whereupon the dog 14 is thrown out from engagement with the tooth 7*, so that the thrust-piece is now supported by the engagement of the tooth 7 with the dog 13. The lever is then moved upward, whereupon the dog 13 moves downward, and with it the thrustpiece. During this movement the dog 1% moves upward and inward to engage tooth 6 and take the weight of the thrust-piece. At the end of this upward movement pawl 21 retracts dog 13 from tooth 7. When the lever 9 is again moved downward, the thrust-piece is retracted one more step. Thus the mere reciprocation of the lever 9 serves to retract the thrust-piece, the latter moving downward step by step for each movement of the lever. It is to be observed that the spring-pawl 22 yields to the pressure of the projection 28 until the weight of the thrust-piece 2 is trans ferred from the dog 14 to the dog 13 and that thereupon the pawl 22 is moved inward by its spring 26 and retracts dog 14, spring 26 being stronger than spring 18 of dog 14. Pawl 21 operates in the same way with reference to dog 13.

32 and 33 are recesses formed in the thrustpiece 2 and into which the pivot-pins 11 and 12, respectively, project, so as to prevent the thrust-piece from turning in the standard.

While I have shown the invention in what I consider to be the best arrangement, it is obvious that many changes in the embodiment of the invention may be made.

hat I claim, and desire to secure by Letters Patent, is-

1. In a lifting device, the combination of a standard; a thrust-piece; a lever pivoted on the standard and provided with spring-pressed clutches; and spring-pressed means movable into and out of cooperating position with reference to said clutches, whereby when said means are out of saidcooperating position each movement of the lever will advance the thrustpiece one step and hen said means are in said cooperating position the reciprocation of the lever will retract said thrust-piece step by step.

2. In a lifting device, the combination of a standard; a thrust-piece; a lever pivoted on the standard and provided with spring-pressed clutches; and spring-pressed abutments designed to engage said clutches and throw them alternately out of engagement with the thrustpiece, said abutments being movable into and out of cooperating position with reference to said clutches, whereby when said abutments are out of said cooperating position each movement of the lever will advance the thrustpiece one step and when said abutments are in said cooperating position the reciprocation of the lever will retract said thrust-piece step by step.

3. In a lifting device, the combination of a standard; a thrust-piece having oppositely-arranged teeth; a lever pivoted on the standard and provided with spring-pressed dogs to engage the teeth of the thrust-piece; springpressed abutments designed to engage said dogs and throw them alternately out of engagement with the thrust-piece, said abutments being movable into and out of cooperating position with reference to said dogs, whereby when the abutments are out of said cooperating position the reciprocation of the lever will advance the thrust-piece, and when the abutments are in said cooperating position the reciprocation of-the lever will retract the thrust-piece.

4c. In a lifting device, the combination of a standard; a thrust-piece having oppositely-arranged teeth; a lever pivoted on the standard and provided with dogs to engage the teeth of the thrust-piece; a ring rotatable on the standard and carrying abutments designed to engage said dogs and throw them alternately out of engagement with the thrust piece, said abutments being movable into and out of co operating position with reference to said dogs, whereby when the abutments are out of said cooperating position the reciprocation of the lever will advance the thrust-piece, and when the abutments are in said cooperating position the reciprocation of the lever will retract the thrust-piece.

5. In a lifting device, the combination of a standard; a thrust-piece having oppositely-arranged teeth; a lever pivoted on the standard and provided with spring-dogs 13 and 14, having projections 27 and 28; a ring rotatable on the standard and carrying spring-pawls 21 and '22- to cooperate with the abutments 27 and 28,

when desired, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CLARENOE W. COLEMAN.

Witnesses:

A. K. GALE, F. K. WINTER. 

